Quinine -- popular remedy for leg cramps -- can be deadly

People who rely on Qualaquin, also known as quinine sulfate, to combat their nighttime leg cramps are putting their lives at risk, warned the Food and Drug Administration. The federal agency issued a warning last week after reviewing reports that spanned from April 2005 to October 2008 in which 38 U.S. patients suffered severe to life-threatening injuries.

Qualaquin was approved by the FDA to treat only malaria, but has remained popular as a leg cramp fix. Of those 38 patients, 25 were prescribed the quinine sulfate drug off-label for leg cramps or for Restless Leg Syndrome. This off-label use has proven to be more harmful than good -- two died, 21 were diagnosed with thrombocytopenia (serious bleeding due to severe lowering of platelets) and were hospitalized, four experienced a condition that could lead to permanent kidney damage, and 10 had adverse effects ranging from hearing loss to an electrolyte imbalance.

"Quinine is an effective treatment for leg cramps but it has potentially deadly side effects," said Dr. Michael Smith, WebMD's chief medical editor, in an e-mail interview with WalletPop. "In fact, the FDA warned against the use of quinine for leg cramps in December of 2006. However, people have continued to use this treatment since there is little else that can help. But due to these serious side effects, and even reports of deaths, the FDA is now warning doctors against the use of quinine for leg cramps."